FATEK M Series User Manual page 8

Chapter 1 List of Expansion Modules
Warning
Do not attempt to dismantle any module or touch the internal side of the module when
it is under energized status or it may lead to electrocution injury.
Do not attempt to touch any terminal or terminal board when the module is under
energized status, or it may lead to electrocution injury.
To ensure the system safety in order to avoid abnormal actions that may be caused by
man-made external factors or false actions resulting from the faulty PLC, it is required to
install the following safety measures in the external circuit (not within the PLC
procedure); otherwise, it may lead to serious accident.
The externally controlled circuit must be provided with emergency stop switch,
interlocking circuit, limit switch and similar safety measures. The PLC will stop outputting
the signals when encountering major failure alarm during the operations. However, the
errors in the I/O controller and the I/O register as well as other undetectable errors will
still trigger unexpected actions. To deal with the aforesaid errors, you are required to
install external safety measures to protect the system safety. If the output relay is
jammed, burnt or if the output transistor is damaged, then the PLC may still maintain its
output at the ON or OFF status.
To solve the aforesaid issues, it is required to install external safety measures to protect
the system safety. By installing the corresponding safety measures in the system and the
equipment, it allows you to maintain the safety of the entire system in spite of the fact
that communication errors or false actions have occurred during the operating process.
The user must take corresponding failure preventive measures in order to ensure safety
when the signal line is damaged or when the power is instantly disconnected or when
the signal is wrong, missing or abnormal as may be caused by other reasons. If failing to
taking the appropriate measures, it may lead to improper operations that may result in
serious accidents.
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M-Series PLC Expansion Module User Manual